Lubricating composition



i atented Feb. 24, 1953 UNITED STATES PATENT OFFICE LUBRICATINGCOMPOSITION corporation of Delaware Application July 1,1947, Serial No.758,430

12 Claims. (01. 252-331;)

This invention relates to compounded lubricating compositions, suitablefor use in substantially all types of industrial equipment, andparticularly in engines operating under adverse conditions.Specifically, this invention pertains to engine lubricants compoundedwith ash-forming improving agents in amounts above .a critical lowerlimit so as to impart to said lubricants outstanding lubricatingproperties.

It is Well known in the art that lubricants whether doped or undoped,deteriorate and form corrosive bodies, sludge, varnish and othercontaminants in engines whether operated under mild conditions (ascharacterized by low temperature and reduced load) or under extremepressure conditions as characterized by high temperature, high speeds,high loads, and the like. Under either condition of operation, factorsare encountered which contribute to oil deterioration with the formationof resultant products of contamination which causes corrosion, sludge,varnish and lacquer formations; this inevitably results in sticking,wearing, soul-Eng, scoring and even seizing of metal parts.

Engine fouling and wear under conditions of high temperature operationis generally attributed to oil deterioration caused by oxidation.Lubricating oils under such conditions tend to oxidize rapidly and formcorrosive bodies and carbonaceous materials which cause scratching orscufling of movable metal parts, sticking of valves, piston rings andthe like. A condition which may accentuate and accelerate-deteriorationof lubricants is the presence of small amounts of moisture existing orformed in lubricants, or blowby vapors from fuel (especially if they arehigh sulfur fuels) which enter the lubricating system and form harmfuldeterioration products, and the like. The close tolerances to whichengine parts are machined as well as the restricted clearances betweenvarious engine parts aggravate this condition and aid in the breakingdown of the lubricant. This is due to the fact that varnish and/orlacquer coatings on various engine parts such as rings, valves, pistons,cylinder walls, etc., caused by oil deterioration, diminish sideclearances, act as heat insulators; both conditions cause increased oiltemperature, resulting in its further breakdown.

Lacquer formations are generally attributed to oil oxidation and arehard resinous materials having a tendency to adhere on metal surfacesandform thereon a hard deposit which blisters and on chipping acts as anabrasive capable of scratching surfaces and blocking oil passages.

,High. temperature and pressure oil decomposition products are highlycorrosive, especially towards alloys such as copper-lead,cadmium-silver, etc. .Other factors can also account for enginecorrosion but they .are complex in nature and varied in origin. Thus,acids, found or formed in oils or fuels may attack and corrodecopperlead bearings or the like. At elevated temperatures alloyedbearings are adversely efiected by sulfur derived from certain of itscompounds or found .free in an oil or fuel. Under these conditionssulfurcan produce hard brittle, black de posits on copper-lead or silverbearings. Such deposits may adhere and reduce the bearing clear ance orthey may break out and gouge out the bearing, in eitherevent resultingin bearing failure.

To Withstand wear and protect bearing surfaces under the above stringentoperating conditions, lubricants must possess so-called extreme pressureproperties whereby-the lubricantby forming a film of low shear strengthby chemical action or physical adsorption on the contact points,prevents metal fwelding and seizure. Generally, lubricantsare quiteincapable of maintaining a continuous protective lubricating filmbetween contacting metal surfaces, unless fortified with special agentspossessing extreme pressuring properties. However, such extreme pressureagents when added in amounts to be effective generally increaseenginedeposits and causewear because of their corrosive nature and activity.

Although oil oxidation is minimized in low temperature operation, enginefouling from other causesis very serious andaggravating. Engine depositsand sludge under these conditions are generally -;associated with oilinsolubles originating from combustion of the fuel oxidation products..11" high suliurfuelsare used, this condition becomesextremely serious,especially if small quantities of water and other contaminants enter thesystem. Low temperature deposit formations are referred-to asrnayonnaise emulsions which contribute toengine fouling and wear. Thepresences of; mineral matter, carbonaceous materials also cause wear andcontribute-toward accelerating corrosivity of metal parts.

To improve thelubricating--properties of mineral lubricatingoilsandsynthetic lubricants it has become the practice to blend with or addto the various lubricants one-and in most cases more than one, additionagents, which have the property of stabilizing and inhibitingdeterioration of lubricants and impart certain beneficial properties tothem. Thus additives have been specifically developed which have theproperty of inhibiting corrosion of alloyed bearings as utilized inautomotive, .dieseland; aircraft engines. Additives have a lso,,bee ndeveloped which possess the property of modifying the carbonaceousmatter formed by deterioration of lubricants, so as to be easilyremoved. Other additives have been developed for the purpose of actingas detergents in lubricants in order to assist in the removal of soot,sludge, varnish, lacquer and the like. Detergents due to their cleaningand dispersing properties prevent the building of deleterious materialson surface and if formed assist in removing them. Still other additiveagents have the properties of inhibiting wear, oxidation; impartoiliness, extreme pressure, properties, act as solubilizers and thelike.

It is an object of this invention to improve the lubricating propertiesof various lubricating bases by addition thereto of a substantial amountof improving agent and/or agents. Another object of this invention is toprovide lubricants with dopes in such concentrations so as to obtain astable, corrosion resistant product even when subjected to the mostadverse operating conditions. Still another object of this invention isto provide a highly effective detergent lubricant capable of preventingringsticking as well as sticking or seizure of other engine parts. It isalso an object of this invention to provide an improved lubricantcapable of preventing wear, scuffing, scratching and the like. Stillanother object of this invention is to provide a stable, non-corrosive,highly detergent heavy duty lubricant suitable for use under varied andadverse conditions. Other objects of this invention will appear as thedescription proceeds.

The art discloses the addition of dopes and improving agents tolubricants in rather very minor amounts particularly in the case oflubricants compounded with a metallic compound. This has been doneapparently due to the belief that because of the pronounced activity ofthe additives or dopes, these latter if used in high concentrationswould become contaminants rather than improving agents and thereforewould act as abrasives, wear, sludge, lacquer corrosion promoters, andthe like. Because of this and also because of the physical modifyingeffects dopes have on base lubricants, such as increased viscosity andthe like, the addition of large quantities of dopes to lubricants hasbeen frowned upon.

The addition of oil dopes in very minor amounts has been rigorouslyadhered to inthe art; for example, U. S. Patents 2,375,222 and 2,410,652state that any additives, such as detergents, when incorporated inlubricants should be in such small amounts as to leave substantially anonvolatile ash upon combustion, and that, at most, the total ashcontent should not exceed about 0.25% (determined as sulfate ash) andpreferably should be below about 0.2% ash by weight. Furthermore, U. S.Patent 2,416,192 discloses that the maximum amount of metallic detergentdope which can be added to lubricants with safety should not be inexcess of 0.42% ash, calculated as sulfate ash. Navy specifications forlubricating oils suitable for diesel engines and the like impose a rigidlimitation as to the maximum ash.

allowable in lubricants. Thus .Navy Department specification 14-0-1301places. as a maximumallowable ash for diesel lubricants at 0.6% ash byweight. above 0.6% ash heretofore havebeen regarded as unsuited becauseof the danger of increased corrosion, wear, etc., particularly in thecase. where metallic salts are used as the dopes.

The desirability of keeping the ash content of lubricants at a minimum,namely, below 0.6 and Lubricants containing an ash content preferablybelow 0.2%, appeared to be a critical limitation substantiated by facts.Thus, within the ranges actually tested heretofore, numerous performancetests such as the CRC tests L1, L2, L3, L4 and L5, as Well as actualfield tests, disclosed that as the ash content increased, corrosivityalso increased at an alarming rate. For example, it was shown that byincreasing the concentration of a metallic detergent in a lubricant from0.2% to about 0.6% wt. ash, corrosivity increased by over 300%. Theaddition of corrosion and/or oxidation inhibitors had little effect onstabilizing or inhibiting corrosivity due to increased amounts of ashforming dopes present. Since such general alarming results wereconsistently obtained with lubricants containing ashforming additives inconcentrations approaching 0.6%, the'practice of doping lubricants withsuch additives in very low concentrations, such as around about 0.2% wt.ash, has been rigorously adhered to.

It has now been discovered that improved engine performance can beobtained by doping the base lubricant with additives employed inconcen-, trations capable of forming ash in amounts exceeding at least1.0% by weight, and up to such large amounts that the only limitingfactor is the change in viscosity characteristics of the base lubricantwhich render it unsuited for engine lubrication. Stated somewhatdifferently, it has now been discovered that the ,corrosivity andinstability of doped lubricants capable of forming an ash increases withincreased concentrations up to a maximum, this range being between 0.2and about 0.8% and higher. However beyond this maximum value, namelybeyond about 1.0% ash,

lubricants become more stable, corrosion progressively decreases, andcleanliness as well as general engine performance is improved. The mostefficient range for doped lubricating oils is when the additive oradditives are in a concentration such that their amounts are betweenabout 1% and about 10% by weight and preferably between about 1.0 and 4%by weight as calculated on the ash basis. With ash forming additiveswhich have little effect on viscosity or gellation of the baselubricant, amounts exceeding 10% and even above 50% by weight ash may beused.

The term ash forming materials comprises such ingredients which ifignited per se or as an oil concentrate, will produce an ash free ofcarbonaceous matter. If certain metallic salts such as of sodium,calcium, etc. are present, the percentage ash may be expressed apercentage of ash as sulfate, while with zinc and aluminum thepercentage of ash is expressed as percentoxide ash. This basis ofcalculation can be accomplished by acidifying the sample tested withdilute sulfuric acid, igniting the sample to free it of carbonaceousmatter and expressing the residue as percent sulfate ash. Thus, forexample, the following procedure may be followed to determine the amountof ash residue in an oil the percent by weight or volume of a dopeconcntra-te, which "can be further diluted or the final percent byweight of a dope in an oil. The above issubstantially the methoddescribed in the ASTM (ES-43) or 1945. I 5

Broadly stated this invention relates to improving lubricants byaddition thereto of ash forming metallic detergents in amounts exceeding1.0% by wt. calculated on the ash basin. The metablic detergent saltsmay be represented broadly by the partial general formula -X-M, ar n-on, or

wherein M is a metal or cationic portion of the salt; X is a part of theanionic portion of the salt to which M is linked to form the metallicsalt; and Q is an element of the group of O, S, Se and Te. I

The metal parts in the above class of compounds may be:

The acid-forming part in the above class of compounds may be: Benzenesulfonic acid Toluene sulfonic acid Tri isopropyl naphthalene sulfonicacid Diphenyl sulfonic acid Polyalkyl aromatic sulfonic acid, e. g. Polyamyl naphthalene sulfonic acid Diwax benzene sulfonic acid Xylenesulfonic acid Benzene disulfonic acid Alkane sulfonic acids, e. g. amyl,octyl, nonyl, 0

lauryl, dodecyl sulfonic acids Petroleum sulfonic acids derived fromvarious petroleum fractions such as:

as Oil kerosene 6 light oil turbine oil mineral lubrication on heavy oilpetroleum waxes, e. g.: 70

petrolatum paraffin wax and mixtures of various hydrocarbon fractionswax sulfo salicylic acid diwax naphthalene sulfonic acidsetc.

eczema Petroleum sulfonic acids are produced by treating suitablepetroleum hydrocarbon fractions with sulfuric acid. For example, aturbine oil having a Saybolt universal viscosity at F. of from about 400to 540 seconds is treated with fuming sulfuric acid, preferably in smallincrements. After a calculated amount of sulfuric acid has been added tothe oil, the sludge which forms is removed and the acid-treated oilcontaining dissolved oil-soluble sulfuric acid is neutralized with asolution of sodium hydroxide. The aqueous alkali solution is removedfrom the mixture and the sodium salts of petroleum sulfonic acidextracted with alcohol. The alcohol layer containing the sulfonates canbe removed by distillation or by any other suitable means.

Modifications to the above procedure can be made by removing acid sludgeafter the entire required amount of acid has been added. Also thesulfonic acid can be removed before neutralization rather than after asindicated above. If this is done, it is preferable to give the acidtreated oil a clay treatment so as to remove inorganic esters ofsulfuric acid and other impurities so as to prevent formation ofinorganic salts. Clays which are particularly suitable are highlyadsorbent clays such as Attapulgus clay, Floridin, bentonite, bauxite,fullers earth, etc. Still another modification in preparmg pureoilsoluble sulfonates is to add to the sludge free acid-treated oil asolvent such as benzol, carbon tetrachloride, and the like and toneutralize said mixture with a caustic solution. The spent causticsolution is removed. The solvent is distilled off, leaving asubstantially pure sulfonate in oil mixture. The product can be airblown and dehydrated to remove impurities. Instead of sulionating amineral oil alone a small amount of waxy material may be added to obtaina more improved sulfonate. The sulfonic acids may be formed byacidifying the neutralized sulfonate or a particularly desired salt of asulfonic acid may be obtained by double decomposition.

Other oil-soluble organic sulfonic acids may be produced by sulfonatingalkyl aromatic hydrocarbons, such as alkyl benzenes, alkyl naphthylenes,alkyl anthracenes, alkyl phenanthrenes, alkyl picenes, alkyl chripenes,alkyl diphenyls, etc., provided the number of carbon atoms in the alkylchain or chains is suificient to render the resulting sulfonic acids andtheir salts soluble in the base. It is desirable that at last one alklyradical be relatively long, i. e. contain at least 8 or more carbonatoms, not only because of solubility in oils, but also for the reasonthat long alkyl chains improve the anti-ringsticking eificiency of thesalts formed with the sulfonic acids. Thus, one may produce an aromatichydrocarbon suitable for the production of highly eflicient sulfonicacids by condensing chlorinated paraffin wax, alkyl chlorides such asoctyl, decyl, cetyl, etc.; chlorides, fatty alcohols, long chain olefinssuch as may be obtained in the cracking of wax, etc., with aromatichydrocarbons by means of suitable condensing agents such asFriedel-Crafts catalysts, sulfuric acid, phosphorus pentasulfide,phosphoric acid, etc. Sulfonic acids may contain substituent radicals asfor example, paraffin'wax substituted naphthalene mono sulfonic acidswhich contain a sulfonic radical attached to one ring'of the naphthalenenucleus and a hydroxy or amino radical attached to the other ring.

Phenolic compounds (R Af-'--X =H) wherein am ss All of these compoundsmay contain substituent groups as listed under VII B and the like.Substituted products are: hydroquinone, quinone, orcinol,phloro-glucincl, cresols, thymol, saligenin, cinnamyl alcohol, methylphenyl carbinol, eugenol, cardanols, etc. Also the thio phenolicderivatives of these phenolic compounds may be used as well as variousreaction products thereof such as obtained by reacting phenoliccompounds with: SC12, S2012, H25, ammonium hydro sulfide H2S, S, S02 andthe like to form sulfide derivatives which may be represented broadly bythe formula:

wherein Ar is an aryl nucleus, R, is an alkyl, andalkyl radical and thelike, X is O, S, Se or Te and u is an integer of from 1 to 4, and Y maybe a polar radical such as listed under VII B either or both m and a: onthe Ar group may be zero or an integer of 1 or 2.

Phenolic condensation products may also be formed by reacting productsunder group IX with aldehydes of the aliphatic, aromatic or cyclic type,specifically represented by formaldehyde, acetaldehyde, crotonaldehyde,butyraldehyde, benzaldehyde; furaldehyde and the like. The condensationreaction is carried out at rather an elevated temperature using an acidor basic catalyst. Typical condensation reaction products may be formedbetween:

Octyl phenol-formaldehyde Octyl phenol-acetaldehyde Iso octylphenol-acetaldehyde Iso octyl phenol-crotonaldehyde Octylphenol-benzaldehyde Octyl phenol-furaldehyde Octyl thiophenol-furaldehyde Octyl thio phenol-formaldehyde Amylphenol-formaldehyde Amyl phenol-furaldehyde Any of the above metallicsalts may be used as well as mixtures of these salts in lubricants whichmay if desired be doped with corrosion and/or oxidation inhibitors.

The following table gives typical examples of preferred normal or innerbasic metallic salts which give outstanding lubricating properties whenused in high concentrations so as to form a high ash, such as above 1%by Weight ash and preferably above about 1.5% and up around about 2.5%ash. Greater quantities of the salts may be used provided the additiondoes not increase the viscosity of the base lubricant abov thatgenerally suitable for engine lubricating. Mixtures of these salts maybe used and the percentage ash may be expressed either as percentsulfate ash, percent oxide ash or as percent ash.

Cation part Lithium Vanadium Sodium Bismuth Calcium Chromium BariumMolybdenum Magnesium Manganese Strontium Iron Aluminum Cobalt Tin NickelLead Acid part Petroleum sulfonic acid Triisopropyl naphthalene sulfonicacid Diaryl naphthalene sulfonic acid Diwax benzene sulfonic acid Diwaxnaphthalene sulfonic acid Benzene disulfonic acid Lauryl sulfonic acidCetyl phenol sulfide Octyl phenol sulfide Octyl thio phenol sulfidePhenol-formaldehyde Condensation product Octyl phenol-formaldehydecondensation product, etc.

Although new. and outstanding improved re-, sults are obtained by addingto lubricants metallic detergents in amounts sufficient to form an ashof above about 1.0% and preferably above about 1.5 and 2.0% and up toabove 2.5% ash or sulfate ash by weight, it is desirable under specificlubricating conditions to admix with said high ash forming metallicdetergent doped lubricants minor amounts of a corrosion inhibitor and/oran anti-oxidant.

The corrosion inhibitors which may be used with high ash formingmetallic detergents of this invention are:

Inhibitors (I-a).-Organic amines (aromatic, aliphatic, alkylaryl,cyclic, heterocyclic amines and their mixtures) Paraphenylene diamineAlpha-naphthylamine Orthophenylene diamine Beta-naphthylamine5-dibeta-naphthyl para phenylene diamine ZA-diamino diphenylamine Metatoluylene diamine 2-amino-1,4-naphthohydroquinone4-amino-1,2-naphthohydroquinone 'Ihiodiphenylamine Monobenzyl para aminophenyl 2,4-diamino toluene 2,4-diamino diphenyl amine Para aminoozobenzene Octadecyl benzyl amine Beta phenylamine-alpha-naphthylaminePhenyl-a-naphthylamine Phenyl-B-naphthylamine N,N' dibutyl paraphenylene diamine Tetra methyl diamino diphenyl methane p,p'-diaminodiphenyl methane 4,4-diamino diphenyl methane -Tetraethyl diaminodiphenyl methane Diisoamyl diamine diphenyl methane Bis (B naphthylamino methyD-p-tertamyl phenol 3,3,5 tricyclohexylamineDicyclohexylamine N-phenyl morpholine N- tparahydroxyphenyl) morpholineOctadecyl B-methyl-Z-pentylandne N-octadecyl-2-ethylhexylamine'Hexadecylamine Octadecylamine Octadecenylamine Octadecadi'enyl amineParaffin waxamine Cocoa-mine prepared from cocoanut oil acidsN,N'-dimethyl triglycol diamine V Disalicylal ethylene diamineN-salicylal-N'-ethanol-ethylene diamine 5 methyl 2,4-diamino anisoleKetone diarylamine Ketone amine Ketone amine condensation productsButyaldehyde aniline derivatives Condensation products of acetone andaniline Reaction products of acetone and para amino diphenyl Inaddition. to the above amine compounds the following mixtures of aminesproduce good stabilizers:

Mixtures of diphenyl paraphenylene diamine and isopropoxydiphenylaminePhenybwnaphthylamine and meta toluylene diamine Mixture of oliparamethoxy diphenyl amine Diphenyl para-phenylene diamine and phenyl betanaphthyl amine Mixtures of phenyl-B-naphthylamine and meta toiuylenediamine Mixture of diphenyl para phenylene diamine and para phenylenediamine Mixture of stearic acid, meta toluylene diamine and pheny-c-naphthylamine Mixture of ditolylamine and petroleum wax, toluidines,xylidines, cymidine, cumidine, pseudo cumidine and the like.

The amines which are particularly preferre are:

Phenyl a-naphthylamine Phenyl-B-naphthylamine Betaphenyiamine-alpha-naphthylamine Tetra methyl diamino diphenyl methane li/feta tcluy'lene diamine, and their mixtures (l-h) .Polycarhoxylicacids:

Oct'yl succinic acid alkylen'e nialonic acid Aikyl alizylene thiomalonicacid Alkyl alkylene glutaric acid Alliyi alk'y lene tartaric acid Alkylalkylene citric acid Cyanc stearic acid Cyano palmitic acid Distearicacid sulfide a-fiexadecyl thio glycolic acid P-phenylene dithiodistearic acid, etc.

,(I-c .'-Partial esters of polyhydric alcoholsf G lyceryi mono oleateGlycol mono propionate Giyceryl mono stearate Biaryl maleate 'Giycerylmono ricinoleate Diaryl succinate Sorbitan mono oleate Diamyl .tartarates Sorbitan mono stearate Sorbitan mono ricinoleate Erythritol monooleate Erythritol mono stearate Mannitol mono oleate Diamyl oxalate(I-d).-Sulfur compounds:

Sulfurized oleic acid Sulfurized sperm oil sulfurized cotton seed oilSulfurized wax olefins Dibenzyl disulfide Bis methylene phenyl sulfideBis methylene tolyl sulfide Butyl arsine disulfide ThiobenzanilideSulfurized mono or dihydric esters of linoleic acid Triphenyl arsinesulfide Sulfo-chlorinated mono esters of fatty acids e. g. reactionproduct of sperm oil and sulfur chloride Thiobenzophenone (I-e).Compounds containing phosphorus:

Triphenyl phosphite Tricresyl phosphite Tributyl phosphite Tricresylphosphate Diethyl phenylphosphinate Ethyl diphenyl phosphinateNaphthenyl phosphi-te Reaction products of substituted phenol PClatricyclohexyl phosphite. Esters containing trivalent P, 'e. g.

R-oH GooR" (I-f) -Compounds containing both sulfur and nitrogen:

O-nitro phenyl thio ethers O-amino phenyl'thio ethers Thio cyano ethersand thio ethers where X is 0 or s, and Y is -CNS or -NCS,

e. g. amyl thiocyano methyl ether Thiob enzanilide Substituted thiazinesand thiazoles e. g. triphenyl thiazole Compounds containing N=C-S--group in ring,

e. g. mercapto benzothiazole Dianiline disulfide Thio andisothiocyanates e. g. lauryl thio and isothiocyanate N-substitutedmorpholines e. g. N-amyl morpholine .7

Di morpholine polysulfides (I-Q) .--Compounds containing both sulfur andphosphorus:

Reaction products of phosphorus sulfide and a phenol or. a polyolefinThioesters of, phosphinous, phosphinic and thiopho'sphinic acidl?hosphatide e.- g lecithin, etc.

(I-f) .--A1ky1 substituted hydroxy aromatic compounds represented by thegeneral formula:

- I -R,.-Ar-OH wherein AT is an aromatic radical, R is an alkyl, alkoxyarylalkyl radical, Y is an organic polar radical, m may be zero orinteger of l or 2 and n is an integer of 1 to 3. Particularly preferredanti-oxidants are the polyalkyl phenols in which the alkyl groups areattached at the 2,6 or 2,4,6 positions. The alkyl radicals which occupythe ortho positions may be methyl, ethyl, nand isopropyl, n, iso,secondary and tertiary butyl, primary, secondary or tertiary amyl,hexyl, heptyl, octyl and homologous radicals. Examples of such polyalkylphenols are:

(I-g).-Phosphorus containing organic compounds:

Phosphatides Chepalin Lecithin (I-h) .Organic acids, other than thoselisted under (I-b): Gallic acid Tannic acid Cinnamic acid Benzoic acidSalicylic acid 7 (Li) .Sulfur compounds:

Thiodiphenyl amine Phenyl sulfide Methyl phenyl disulfide Phenyldisulfide Ethyl sulfide Benzyl disulfide, etc. Benzyl sulfide Waxdisulfide (1-9) .Terpenes:

Pine oil Rosine oil Turpentine oil, etc.

(I-k) Organic compounds containing halogen Halogenated diphenylene oxideHalogenated acid-diphenylene oxide condensation product Condensationproduct of two halogenated fatty acids Condensation product ofhalogenated wax halogenated organic acid v Halogenated wax condensationproduct Halogenated ring compound such as o-dichlorobenzene Halogenatedhydrocarbons e. g. chlorinated hexane Chlorinated diphenyl benzene Monoand dichloro derivatives of xylyl-, phenyl-,

decyl-, and tolyl hepta decyl ketone Halogenated naturally occurringesters chlorinated carnauba wax Phthalic acid Uric acid Fureic acidAbietic acid The amount of anti-oxidant and/or corrosion inhibitor ifadded to a base oil containing a 5 Minimum i Maximum Average Enginespeed, R. P. M 3 130 3, 165 Engine load, B. H. P to. s 30v 5 28 OilTemp. in Sumo, 277 284 280 7 Oil pressure, p. s. i 13.5 14.1 13.8 Jacketoutlet coolant te 197 203 199 Exhaust pressure, in Hg 0. 7 0.9 0. 8Intake depression, in Hg 12. 2 12. 8 12.5 Fuel consumption, sec. per 300metallic detergent in amounts sufiicient to form an ash at least aboveabout 0.8%, is generally less than 1% by weight, although greaterquantities may be used. 'The preferred range is between about 0.1% andup to about 5% by weight, depending upon the oil base, concentration ofthe metallic detergent and condition of use.

Base oils may be selected from a wide variety of natural oils such asparaifinic, naphthenic and mixed base oils having a wide viscosityrange, such as a minimum of at F., S. U. S. up to 250 at 210 F., S. U.S. In addition synthetic oils may be used such as polymerized olefins;copolymers of alkylene glycols and alkylene oxides; organic esters, e.g. Z-ethyl hexyl sebacate, dioctyl phthalate, trioctyl phosphate;polymeric tetra hydrofuran; polyalkyl silicon polymers, e. g. dimethylsilicon polymer, etc. Mixtures of natural and synthetic oils can be usedalso. Under certain conditions of lubrication minor amounts of a fixedoil such as castor oil, lard oil and the like may be admixed with ahydrocarbon oil and/or with a hydrocarbon oilsynthetic oil mixture.

To more fully illustrate the present invention the following are a fewexamples of compositions of this invention which have been compounded inhigh concentrations with ash forming metallic detergents and inhibitedagainst corrosion and/or stabilized against oxidation deterioration andfound extremely effective for heavy duty lubrication. The base oil usedfor test purposes was an SAE 30 oil having a viscosity index of 55. Highash containing compositions of this invention passed the CRC tests L-l,L-2, L-3 and L-4 as described in the CRC handbook under the chapterdescribing engine oil tests. For purpose of illustration the followingtest results of oil compositions of this invention are listed whensubjected to a CRC test L-4-545, which is a 36-hour test in a Chevroletengine using the following conditions:

base 011 being inhibited with an anti-oxidant 5 perature of 100 and/ orcorrosion inhibitor.

Tns'r II A reference oil and an oil of this invention were subjected toa CRC L-l, at a water jacket tem- F. and at standard operatingconditions with a fuel containing 1.06% sulfur.

TABLE .1

BASIC OIL 600 SUS AT 100 F. MOT-OR STOCK a (321 2 6 d't t .cmm cium 1 orsalt of Salt .0: 23 butyl Bearing vise inc Petroleum Petroleum g 4methyl Weight Piston Overall bs Sulfonate, Sultanate, phenol. Loss,Rating Rating Percent" ,Percent Percent Wt Percent mg. Sulfate 'Sull'ateWt.

.As vAsh 0. 2 501 4 66 82 0. 2 872 8 90. 5 1.00 0. 2 l, 000 8 90. 5 100O. 2 516 99. 5 96 0. 2 197 9. 5 99. 5 8O 0. 2 70 9. 5 99. 5 S 0. 3 0. 2532 7% S4. 80 0. 6 VO. 2 750 8 92 0.9 0. 2 1, 260 9+ 99 90 1.2 0. 2 1,312 10 100 130 l. 7 O. 2 282 10 100 81 2. 3 0. 2 64 10 100 104 5. 8 0. 2l 22 10 100 0. 3 0. 2 0. 7 570 5 81% 69 0. 6 0. 2 0. 7 810 10 99% 80 1.20. 2 O. 7 350 10 100 48 This data. is graphically presented !by curvesin Figures I, II and III. In each of these curves of Figure I, it can beseen that hearing corrosion increases drastically with increasedconcentrations of detergent until a maximum is reached and thereafterthe bearing corrosion unexpected- 1y begins to decrease with increasedconcentrations of detergent. Since the corrosion increases well past0.6% by weight ash it can be seen why the general conjecture in the artis that corrosion would continue to increase with increasedconcentration of detergent and the apparent reason why the U. S. Navyand Army specification placed an arbitrary critical limit of 0.6% byweight ash as the maximum allowed for engine lubrication. However it hasnow been discovered that past a critical upper limit corrosion and wearbegin to decrease with increased amounts of detergent. Thus the valuablecontribution of this invention that increasing the concentration of adetergent past a critical upper corrosion limit wear and corrosion canbe substantially inhibited. Furthermore not only the corrosive and weartendencies of lubricants diminished in this manher but enginecleanliness and performance is greatly improved as can be seen byreferences to Table I and Figures 11 and III.

Analysis of the reference oil and high ash oil were as follows:

High Ash Reference oil, referred Oil to as Composition 18 1 Gravity. "A.P. I. at 00 23. 5 Flash, 0. O. 0., "F"... Fire, F Viscosity, S. S. U. atI Viscosity, S. S. U. at F Viscosity, S. S. U. at 210 F- Viscosity IndexAniline Point, "F Sulfur, percent... Insol. P. E., Mg/g. Oxide ash,percent.

Carbon Residue, perce 0: 38 Neut. No 0. 11 all: Strong Base No., M 0. 40alk Free Acidity, Mg/g.

1 Calcium petroleum sulfonate, 2% weight sulfate ash; P11931311:-naphthyl amino, 0.2% weight; 2,6 ditert. butyl-i-methyl phenol, 0.7%weight.

RESULTS OF L-l ENGINE TEST L-l Except 100 F. Water Temperature EngineCondition Reference Oil Piston rings medium deposits Grooves mediumdeposit of hard carbon and lacquer. Lands 100% Black lacquer-..

Under-side Crown Covered with black lacquer. Ring Wear-Top ring. 0.050"gap increase. Liner Wear Transverse 0.0049" longitudinal 0.0095

L'l Operating Condition Composition B of Composition B or this inventionReference 011 this invention All free and olezmm. Heavy deposit ofsludge All free and clean.

around oil ring supports and along bottom rail. Clean Covered with blackClean.

lacquer and medium de osit ofhard carbon. 100% clean 100 a covered withblack Do.

lacquer. Clean Covered with dark Do.

brown lacquer. 0.011 gap increase. 0.028 gap increase 0.013 gapincrease.

Tiss'r III An actual field test in a caterpillar D-4600 engine driving awater well. pump and using a high sulfur fuel was operated for a periodindicated in the table below using the best available heavy dutylubricant identified in the table as reference oil A which contained ametallic detergent in Phenyl-a-napthylamine, percent weight 2,6ditertiary butyl-4-methyl phenol, percent weight.

lubricants the acidic materials as they formed are taken up by thealkaline reserve agent-thereby preventing sludge formation, whereas inlow ash doped lubricants there is insufiicient neutralizing materialcapable of taking up or neutralizing the acidic decomposition materialsas they are formed. Increased amounts of sludge on the other handinactivate the detergent ingredients in the lubricants or admixed withit and the entire mixture is removed as a contaminant.

I'he unexpected results obtained using a high ash doped oil are furtheriliustrated by subjecting an S. A. E. motor stock oil of VI and dopedwith various amounts of a basic calcium petroleum sulfonate. Oils thusdoped were subjected to a Dornte oxidation test as described in theIndustrial and Engineering"Chemistry,vol. 35, page 581, 1943, using0.05% wt. crankcase catalyst, and at a temperature of 150 F., the

Average cylinder wear Condltlon of lungs mm Composition Time grooves andpistons Run 1 Reference Oil A Heavily fouled with sludge. Runz{Reference OilA 500 r..

---- Composition B. 1,050 hr. after engine was run for 0.005 in totalactual wear... Engine absolutely clean.

500 hr. on Reference Oil A.

Analysis of composition B before and after Used oil Used oil l g a after1050 after ecnhr. trifuged Gravity. A. P. I Flash, P. M. cc., F

Flash, 0. O. (3., F 4 Viscosity, S. S. U. at 100 F.... 579 (i Viscosity,S. S. U. at 210 F.. 61. 0 64. Viscosity Index "i 63 Initial pH l0. 7 6.i 0. 3 'IBN-E, mg. KOH/g 5. 2 0.2 0.2 AN-E, mg. KOH/g 0.8 0 1.0 OilInsolublos, per cent v nil 0.2 Isopentane Insolubles, pe

weight nil 0.2 Benzol Insolubles, percent Wt.. nil 0. 2 I SaponificationNo., mg. KOH/g. 1.0 alk 3. 0 3. 7 Sulfa-ted Ash, percent Wt 2. 1 2. 2 2.3

1 Oil diluted with equal volume petroleum ether, centrifuged at 6000 R.P. M. for 3 hour and volume precipitate measured. Petroleum etherevaporated from oil prior to subsequent testing.

The above figures are highly significant and illustrate perhaps thereason for the unexpected results obtained using a high ash doped .oil.Thus as indicated above the initial new oil had an initial case numberby electrometric titration (TEN-E) of 5.2 and after 1050 hours of usedropped to 0.2"indicating that the basici-ty of the oil was beingdepleted. Also the average total acid number (TAN-E) increased from 0.8to 5.0 indicating further formation of acidity materials. However thetotal sulfat ash, in the new and used oil remained substantiallyconstant. This. sulfate ash apparently acts as an alkaline reservereacting with acidity materials as they are formed thereby preventingthe formation of corrosion, sludge and the like. On the" other hand withlow ash doped lubricants the formation of acidic decomposition productstakes place without the presences of any reagent capable of acting inthe capacity of an alkaline reserve agent. Another surprising factor isthat whereas with high ash doped lubricants of this invention the activemetallic detergent remains substantially constant acting in the capacityof an alkaline reserve agent, in the case of low ash doped lubricantsthe metallic detergent becomes depleted rapidly and after relativelyshort period of use. It appears that with high ash doped time requiredto absorb 1500 ml. of oxygen noted. Figure IV discloses the resultsobtained and i1- lustrates once again applicants basic discovery. Thusit can be seen that up to a critical value of around about 0.8% wt. ashthe oxidation stability of doped oils decreases with increasedconcentrations, but that past the critical value oxidation stabilitycontiues to increase with increased concentrations of metallicdetergent.

TEST IV In two CFR engines used for evaluating the octane rating ofaviation gasolines, normally compounded heavy duty lubricating oilsallowed deposits to accumulate on the piston to an extent whichinterfered with operation. A large increase in the amount of ash formingadditives in lubricating oil reduced deposits between nor- H maloverhaul periods to a negligible amount as is shown in the tablefollowing: v

CPR-AFD F2 ENGINE BASE OIL (55 VI MOTOR STOCK OIL) Ca petroleumsulionate, percent wt. ash; 0. 27 Sulfurized sperm oil, percent wt 3.00Ihenyl-a-naphthylamine, percent wt. Engine Deposit in 200 hrs TEsT VSpiral test procedure (a) A test sample reservoir, a ml. separatoryfunnel, is filled with the oil to be tested and weighed to 0.1 gram on abeam balance. The reservoir is then placed in position with the tip ofthe calibrated capillary just above the opening in a feed lead tube, andthe oil flow rate controlled at 0.5 gram per minute by a previouslycalibrated glass capillary tube,

(13) A prepared spiral is slipped over the heater and-thermocouplesattached to the screws on the periphery of the spiral.

(c) A tared 100 milliliter beaker is placed in position under the spirallead ofi tube to recover the unvolatilized oil.

(d) Current is applied to the spiral heater through a standard voltvariable transformer (A Varitram, Model V-1M,- equipped with a voltmeterhas been found very satisfactory for controlling the power input) (e)Power input is adjusted so that the averspiral temperature to agetemperature of the thermocouples is 280 C.

(variation from the average for any one thermocouple should not be morethan 10 degrees).

,may be made by taking a drop count during the run. (h) At the end of100 minutes the oil flow is stopped and the power to the heater isturned I 1 -Reporting of results (a) The charge reservoir is reweighedand the weight of sample used is recorded.

(b) The recovered oil beaker is reweighed and r the per cent sample loss'(volatilized) is reported.

( c) 'The spiral is allowed to cool and then is slipped off the heaterand washed by dipping gently in isopentane until successive washings arecolorless. The washed spiral is then dried in an oven at 100 C. forapproximately thirty minutes, cooled to room temperature and revveighedto the nearest milligram.

(d) Any insoluble deposits that flake ofi the spiral during the washingare recovered by filtering the isopentane through a tared sintered glassfilter. These deposits are dried at 100 C. for thirty minutes,cooled toroom temperature, and their weight determined.

(e) The milligrams increase in spiral weight plus the weight, inmilligrams, of any deposit recovered from the washings divided by thegrams sample charged is reported as milligrams deposit per gram at (testtemperature) and the results of a spiral test on various concentrationsof Ca petroleum sulfonate in mineral oil and composition (referred to incolumn 13) are represented graphically in Figure VI. Once again it canbe seen that an oil is improved with increased concentration of an ashforming salt.

Spiral test results on mixtures of Ca petroleum sulfonate and Ca octylphenol-formaldehyde condensation product are listed below. It will benoticed that as the concentration of the additive mixture increases to amaximum deposit formation also increases, but thereafter as the additiveconcentration is increased deposit formation decreases.

serRA DEPOSIT petroleum sulfonate and Ca octyl phenolformaldehydecondensation product in mineral lubrication oil.

Totaltldilfitwyger- Additive a e s Adddtrves Ratio None 7. Ca petroleumsulionate 7. 5 3 1 2 5 1 0 Ca octyl phenol-formalde condensation product7. 5 4. 5 2. 7 2. 4 Ca petroleum sulionste 3 Ca octylphenol-formaldehyde 7. 5 2. 4 2. 2 1.0

condensation product. l 1 Ca petroleum sulionate 1 0a octylphenol-formaldc de 7. 5 5. 2 2. l 0. 9

condensation product 1 Ca petroleum sulicnete 1 Ca octylphenol-formaldehyde 7. 5 5.0 3.0 1.0

condensation product 3 Improvement of lubricants doped to a high ashvalue is also illustrated in the Thrust Bearexpected results.

55 VI, SAE 30 motor oil containing 0.2% wt.

PHENYL-a-NAPHTHAMINE Concentration, percent sulfate ash CriticalCorrosion Temp, "0

Add ltive S. A. E. 30 MINERAL OIL Ca salt of alkyl phenol-formaldehydecondengetion product Do Ba salt of alkyl phenol sulfide Ca salt of alkylphenol sulfide Specific salts and inhibitors referred to in the aboveexamples were only used for illustrative purposes and are not to beconstrued as limitations of this invention, the present basic inventionbeing that lubricants doped with ash forming compounds inhighconcentrations of above 0.6% by weight ash produce improved and un-It is therefore to be understood that while the features of theinvention have been described and illustrated in connection withspecific compositions, the invention is not to be limited thereto orotherwise restricted, except by the prior art and the scope of theappended claims.

We claim as our invention:

1. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubricating oil; a calcium salt of petroleum sulfonic acid in an amountof from about 1% to about 4% calculated as sulfate ash and minor amountsof from 0.1% to about 1% by weight of phenyl alpha naphthylamine and 2,6ditertiary butyl-amethyl phenol.

2. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubricating oil; a calcium salt of a hydrocarbon aromatic sulfonic acidin an amount of from about 1% to about 4% calculated as sulfate ash andminor amounts of from 0.1% to about 1% by weight of an aryl amine and analkyl phenol.

3. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubrieating oil, a basic calcium salt of petroleum sulfonic acid in anamount of from about 1% to about 4% calculated as sulfate ash and minoramounts of from 0.1% to about 1% by weight of phenyl alpha naphthylamineand 2,6-ditertiary butyl-d-methyl phenol.

4. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubricating oil, a basic alkaline earth metal salt of petroleum sulfonicacid in an amount of from about 1% to about 4% calculated as sulfate ashand minor amounts of from 0.1% to about 1% by weight of phenyl alphanaphthylamine and 2,6-ditertiary butyl-l-methyl phenol.

5. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubricating oil, a basic alkaline earth metal salt of petroleum sulfonicacid in an amount of from about 1% to about 4% calculated as sulfate ashand minor amounts of from 0.1% to about 1% by weight of an aryl amineand an alkyl phenol.

6. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubrieating oil; a calcium salt of a petroleum sulfonic acid in anamount of from about 0.8% to about 4% calculated as sulfate ash and aminor amount of from 0.1% to about 1% by weight of phenylalpha-naphthylamine.

7. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a mineraloil, a metal salt of a hydrocarbon aromatic sulfonic acid in an amountof from about 0.8% to about 4% calculated on an ashbasis and a minoramount of from 0.1% to about 5% by weight of an aryl amine.

8. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubrieating oil, a calcium salt of petroleum sulfonic acid in an amountof from about 0.8% to about 4% calculated as sulfate ash and minoramounts of from 0.1% to about 5% by weight of phenyl alpha-naphthylamineand sulfurized sperm oil.

9. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubricating oil, a mixture of a calcium salt of petroleum sulfonic acidand a calcium salt of a condensation product of octylphenol-formaldehyde, the mixture of said salts being in the ratio of 1:3to 3:1, respectively, and in an amount of about 1% calculated as sulfateash and minor amounts of from 0.1% to about 1% by weight ofphenylalpha-naphthylamine and 2,6-ditertiary butyl-4- methyl phenol.

10. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubricating oil, a mixture of an alkaline earth metal salt of petroleumsulfonic acid and an alkaline earth metal salt of a condensationproductof octyl phenol-formaldehyde, the mixture of said salts being inthe ratio of 1:3 to 3:1, respectively, and in an amount of about 1%calculated as sulfate ash and minor amounts of from 0.1% to 20 about 1%by weight of phenyl-alpha-naphthylamine and 2,6-ditertiarybutyl-4-methyl phenol.

11. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubrieating oil, a mixture of an alkaline earth metal salt of petroleumsulfonic acid and an alkaline earth metal salt of a condensation productof octyl phenol-formaldehyde, the mixture of said salts being present inthe ratio of 1:3 to 3:1, respectively, and in an amount of about 1%calculated as sulfate ash and minor amounts of from 0.1% to about 1% byweight of an aryl amine and an alkyl phenol.

12. A finished liquid lubricating composition for use in enginesoperating on high sulfur fuel comprising a major amount of a minerallubricating oil, a mixture of a calcium salt of petroleum sulfonic acidand a calcium salt of a con densation product of octylphenol-formaldehyde, the mixture of said salts being present in theratio of 1 :3 to 3: 1, respectively, and in an amount of about 1%calculated as sulfate ash and a minor amount of from 0.1% to about 5% byweight of phenyl-alphanaphthylamine.

ROBERT C. BARTON.

ROLAND F. BERGSTROM.

JACOBUS M. PLAN'IFEBER.

REFERENCES CITED The following references are of record in the file ofthispatent:

UNITED STATES PATENTS Number Name Date 1,630,101 Wilkin May 24, 19272,109,779 Morway Mar. 1, 1938 2,169,155 Lincoln Aug. 8, 1939 2,330,239Prutton Sept. 28, 1943 2,361,476 Higbee Oct. 31, 1944 2,361,804 WilsonOct. 31, 1944 2,375,222 Griflin May 8, 1945 2,383,033 Adams Aug. 21,1945 2,412,633 Schwartz Dec. 17, 1946 2,412,634 Schwartz Dec. 17, 19462,402,325 Griesinger June 18, 1946 2,410,652 Grififin Nov. 5, 19462,416,192 Mertes Feb. 18, 1947 2,420,893 McNab et a1 May 20, 1947FOREIGN PATENTS Number Country Date 115,356 Australia July 2, 1942

1. A FINISHED LIQUID LUBRICATING COMPOSITION FOR USE IN ENGINESOPERATING ON HIGH SULFUR FUEL COMPRISING A MAJOR AMOUNT OF A MINERALLUBRICATING OIL; A CALCIUM SALT OF PETROLEUM SULFONIC ACID IN AN AMOUNTOF FROM ABOUT 1% TO ABOUT 4% CALCULATED AS SULFATE ASH AND MINOR AMOUNTSOF FROM 0.1% TO ABOUT 1% BY WEIGHT OF PHENYL ALPHA NAPHTHYLAMINE AND 2.6DITERTIARY BUTYL-4METHYL PHENOL.